The National Survey of Multiple Sclerosis (NSMS) is a probability sample of all multiple sclerosis patients in the conterminous United States. The Survey gathered detailed data on the disease, employment, and social history of over 1200 cases. The Office of Biometry and Field Studies in conjunction with other researchers in the field of multiple sclerosis is undertaking a detailed analysis of these data. It is hoped that some concept of how disease factors affect the lives of these individuals will be obtained.